Page 8 - Energize November 2022
P. 8
NEWS
A breath of fresh air for a mining company
Sasol Mining relies on Relion to ensure reliable power supply to new ventilation shaft
asol Mining chose in favour of reduction. For the new substation that feeds the new ventilation shaft, Sasol Mining
the highly flexible ABB Relion® chose a protection and control solution with ABB’s Relion relays from the product
Sprotection relays for their new family’s 615 and 620 series, as well as the all-in-one protection relay REX640 to be
substation at the Syferfontein mine in installed in the medium-volt-age switchgear. This is the first installation with ABB’s
South Africa. The wide functionality, Relion® protection and control relays for Sasol Mining.
large event and fault recording “A key consideration for us when deciding in favour of the Relion® relays was that
capabilities, reduced footprint, as they offered all the functionality we need,” said Divesh Ramasur, Senior Electrical
well as cost reductions, were the key Engineer at Sasol Mining. “They are also flexible and offer large event and fault
factors. recording capabilities.”
Sasol Mining is part of South Sasol Mining chose these protection and control relays because they offer the
African integrated energy and needed circuit breaker control functions and have arc flash protection embedded for
chemical company Sasol, undertaking increased safety. They also have simpler GOOSE (Generic Object-Oriented Substation
the coal mining operations. Sasol Event) protocol utilisation and all have the R/L (remote/local) switch available on the
Mining operates six coal mines that relay faceplate for easier operation. Further, the customer chose Relion 620 series
supply approximately 40 million tons relays for motor protection. These relays offer stall protection functionality and also
per annum of thermal coal feedstock. thermal overload protection considering the actual starting time of the motor.
At the company’s largest colliery, the The installation of Relion relays has resulted in cost reduction and reduced
Syferfontein mine in the Secunda switchgear footprint. “With REX640 we can use only one relay for transformer
area, Sasol Mining identified that the protection, whereas earlier we had to use many different relays to achieve the same
ventilation shaft was not sufficient level of protection,” said Ramasur. “The REX640 relay has many protection functions
to ensure the required aeration available for transformer protection, such as low impedance differential protection,
of the mining district. To ensure low impedance restricted earth-fault protection, sensitive earth fault protection, and
uninterrupted power supply to a new tap changer control all integrated into the relay. On top of that it has many binary
ventilation shaft, they needed a new inputs and outputs, and the relay can incorporate many analogue inputs, too.”
substation. As a result, the footprint of the switchgear was reduced, as there was no longer
In underground mining, the need to install three different relays to obtain the same functionality. The smaller
ventilation systems are of paramount
importance to ensure safe working
conditions for people. Ventilation
systems provide clean air, dilute
and remove dust as well as natural
and machine exhaust gases, and
provide cooling for personnel and
machinery. Ventilation systems need
to run continuously 24 hours a day,
throughout the year, which means
uninterrupted power supply is a key
requirement. The energy demand is
significant and ventilation systems
are currently the largest consumers
of power in underground mines,
accounting for as much as 50 percent
of energy use.
ABB’s protection and control
solution offers the needed
functionality and flexibility – with cost
energize | November 2022 | 8